Radiating cable for indoor localization using UMTS

Abstract

A severe drawback of using RF (Radio Frequency) Fingerprinting for indoor localization is the laborious effort to calibrate the radio map. Especially in case of environmental changes recalibration becomes necessary. The approach of our research project WIPoS (Wireless Indoor Positioning System) is to solve this problem by appropriate RF engineering and optimized methods. In former publications it has been shown that using leaking feeder cables using wireless local area networks (WLAN) has an important advantage that the fingerprints are more insensitive to environmental changes than using omnidirectional antennas. This paper compares the performance of two different types of leaky feeder cables in a long hallway scenario using UMTS and WLAN as wireless system technologies. We can show that using radiating cables have some advantages versus omnidirectional antennas and that UMTS is an alternative system technology to WLAN for RF-Fingerprinting.

Position Estimation in Corridors Along the Coupled Mode of Radiating Cables

“… is the maximal value of this parameter in the series. Both the mean value and standard deviation of the position estimation errors were comparable to results presented by other authors for systems with narrowband signals [ 17 ].…”

“…However, different power measurement results are caused by longitudinal signal attenuation in the radiating cable which corresponds to terminal position. The same authors described [ 16 , 17 ] a solution based on signal transmission in opposite directions, i.e., two ends of the radiating cable connected to two wireless local area network (WLAN) access points. Signal levels were measured by the terminal located in a long hallway near the radiating cable and compared with a previously prepared radio map.…”